Erin Cummings, who has played Spartacus' enslaved wife on Starz's Spartacus: Blood and Sand, has joined the cast of CBS' drama pilot Baby Big Shot. The project, from writer Dana Calvo, showrunner Kevin Falls, Sony TV and Jamie Tarses' Fanfare, is a legal drama centered on Martina (Janet Montgomery), a working-class woman who uses her street smarts to compete with her more polished colleagues at a top New York law firm. Cummings will play Martina's sexually heightened older sister. The actress, repped by Untitled Entertainment, was recently seen in the film Bitch Slap, which premiered at the Toronto Film Festival, and in a recurring role on ABC's Pan Am. She just wrapped the feature Iceman.